JSON Expert
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Meet FRATCH Experts who have recently used JSON
William N.
Last position:
Power BI Solutions Architect/Engineer & AI Consultant at AVERDUNG GmbH
- Redesign of the company's BI infrastructure: replacement of a fragmented landscape of manually maintained Excel solutions and CSV imports with a centralized Power BI environment featuring a unified data model as the company-wide single source of truth
- Consolidation of previously isolated reporting logic into a central semantic model – eliminating redundant files, manual data transfers, and inconsistent metrics between departments
- Forecasting & planning: Design and implementation of company-wide liquidity planning in Power BI – from business logic to a fully automated, data-source-driven planning model replacing the previous manual Excel process; enables rolling forecasts and continuously up-to-date cash flow transparency for management
- Optimization of existing Power BI dashboards in terms of performance, structure, and analytical value using an AI-native approach
- Analysis and improvement of the data model, including data quality analyses, data cleansing, and consistent modeling using star schema, DAX, and Power Query
- Incident & anomaly analysis: Identification, investigation, and explanation of data anomalies, including root-cause analysis and concrete recommendations for action
- AI solution architecture: Connecting Business Central and Power BI to LangDock via MCP (Model Context Protocol) for AI-supported data usage
- Creation of a historical data layer as a basis for trend and time-series analyses
- AI-supported automation: Design and development of AI skills, agents, loops, and processes for the automated analysis and interpretation of reports
- Automated reporting workflow: Setup of scheduled, automated email distribution of AI-generated analyses and recommendations to stakeholders
- Gathering and documentation of business requirements and coordination with business departments and IT as part of requirements engineering / product owner activities
- Breaking down overall requirements into clearly defined work packages and tasks
- Definition, prioritization, and management of milestones throughout the entire project lifecycle
Tools: POWER BI, M365, Copilot Studio, MIRO, Microsoft Business Central, Microsoft Fabric, Claude AI, ChatGPT, LangDock, MS VS Code
Florian S.
Last position:
AI Product Manager / Product Owner at AI Product
- Generative AI products for corporate clients, owned from strategy through specification to production.
- Central strategy, local configuration: multi-tenant AI assistant for occupational pension schemes (bAV), delivered as an interactive avatar with text and voice path. Three tenants run on one codebase, each with its own conversation guide, while the knowledge base, guardrails and escalation paths stay central
- Versioned, AI-ready knowledge base composed into a tenant-agnostic voice context and tenant-specific text prompts — the configuration layer that keeps local adaptation from forking the product
- Conversational design: answer limits, scope and off-topic handling, anti-hallucination rules, escalation and lead handover to human advisors
- Five eval suites as a quality gate before any prompt or model change (anti-hallucination, LLM-as-judge failure modes, multi-turn consistency, voice KPIs, action vocabulary with confusion matrix); user test with 10 testers (Hamburg, 07/2026) drove the rework from alpha to beta
- Coordinated external developers, compliance and client stakeholders; GDPR-compliant EU stack, IDD-compliant, EU AI Act classification documented
- Second product line: white-label social media generator for consultancy chilli mind (CH/DE) — one codebase, per-client branding and configuration
- Results: 239+ deployments and a pilot with corporate customers · 108+ deployments for the white-label product · repeatable pattern for multi-tenant AI products in a regulated environment
Onur K.
Last position:
Project Manager & Outsourcing Manager at SENEC GmbH (EnBW Group)
- Built a scalable nearshore IT developer hub (Croatia, Czech Republic, Poland) as an independent company through a BOT model (Build – Operate – Transfer)
- Identified, selected, and managed full-service agencies; introduced management and control mechanisms, including KPIs, SLAs, and regular service reviews
- Prepared and reviewed data processing agreements and framework contracts in coordination with Legal & Compliance; integrated regulatory requirements (including KRITIS) into process design
- Advised on cloud vs. on-premise strategies, data storage, and authorization concepts; supported Procurement with tendering and service provider evaluations
- Managed change and process harmonization between internal teams and nearshore partners; reported to executive management, CFO, and CIO
Result: Scalable IT developer hub with an audit-ready governance model, reduced operating costs, and accelerated product development.
Wolfgang O.
Last position:
Project Manager at EnBW - Netze Südwest
- New development and further development of the existing MS Dynamics CRM
IT systems: Microsoft Dynamics Customer Service, SharePoint, DevOps, SAP IS-U
- CRM implementation / further development
- Taking over from the previous service provider
- Business process analysis
- Agile project organization
- Business analysis / requirements engineering with AI support
- Use of AI in development
- Analysis of master data processes
- CRM customer data management
- Requirements documentation
- Stakeholder management
- Workshop moderation
Collin K.
Last position:
Software Architect / Fullstack Developer at Equity Bytes
Built an international e-commerce platform for a multi-vendor marketplace for digital assets from scratch. Designed and operated cloud native architectures at enterprise scale.
- Designed and operated a highly scalable microservice and serverless architecture
- Built the complete cloud infrastructure with Terraform + AWS CDK in AWS
- Provisioned ECS/EKS clusters (Fargate), Application Load Balancers (reverse proxy), and Lambda functions
- Observability & tracing with CloudWatch, DataDog, Prometheus, and Grafana
- End-to-end setup with DataDog (formerly AWS CloudWatch), Prometheus, and custom Grafana dashboards
- Integration of advanced metrics (including ORM mapper) and distributed tracing with Jaeger
- Robust backup and disaster recovery strategies
- RDS Postgres backups and hourly snapshots
- Read-only, asynchronously synchronized replicas with automated master failover in emergencies
- Minute-level rollback capability through versioned Docker images on ECS and Git-based CI/CD pipelines
- Created CI/CD pipelines with GitHub Actions for automated multi-stage deployments (Dev, Testing, Prod)
- Integrated Stripe for international payment processing
- Built a marketplace payment system with multiple parties and payout routines
- Used Algolia for high-performance real-time search of digital assets on the platform
- Federation of services with GraphQL and Hasura
- Later migration to GraphQL Mesh
- Test Driven Development (TDD) - unit, integration, and E2E testing with Jest, Vitest, and Playwright
- Used Next.js / React for modern frontend applications in the nx monorepo
- Enterprise security architecture & access control
- Integration of JWT tokens with Auth0, OAuth, OIDC, IP guards, BOLA protection, and secret vaults
- Authorization concepts with RBAC, ABAC, and native Postgres Row-Level Security (RLS)
- Built internal microfrontends with Retool for fast prototyping and operational business processes
Technologies: ABAC, AWS CDK, AWS CloudWatch, AWS ECS, AWS EKS, AWS Fargate, AWS RDS, AWS S3, Algolia, Auth0, DataDog, Docker, GitHub Actions, Grafana, GraphQL, GraphQL Mesh, Hasura, JWT, Jaeger, Java, JavaScript, Jest, Kotlin, Kubernetes, Monorepo, Next.js, OIDC, Playwright, Postgres, Postgres RLS, Prometheus, RBAC, Redis, Retool, Serverless, Stripe, Terraform, TypeScript, Vitest
Olga L.
Last position:
Business Analyst at VisualVest (Union Investment)
- Analyzed, structured, and documented business requirements for digital investment solutions, such as robo-advisors.
- Designed applications for new retirement products, including user flows, UX requirements, and functional specifications.
- Modeled and optimized business processes and coordinated with stakeholders while taking regulatory requirements in the financial sector into account.
Bruno P.
Last position:
Product Owner
Design and implementation of a „unified-commerce“ platform for SMEs to sell and deliver multi-product bundles
Achievements: On-time design, delivery and customer acceptance of a 100% functional, CPQ-based „buy flow“ process for configuring and selling multi-product bundles within the specified time frame of 90 days. Successfully tested integration of various interface services for: customer search, enrichment of customer data, address validation, service qualification, phone number validation, credit check, appointment selection and Quote-to-Order transition.
Responsibilities:
- Strategic goal implementation: Derivation and implementation of strategic customer goals (e.g. release content, business value).
- Backlog Management: Creation and elaboration of backlog items (Initiatives, Epics, User Stories, Defects) in close coordination with the project team and customer.
- Prioritization & Releases: Responsibility for prioritizing the Product Backlog and implementing defined release goals.
- Deliverable Tracking: Tracking work results on the supplier and customer side.
- Roadmap & Release planning: Development and implementation of roadmaps and release plans together with the customer.
- Scope responsibility: Responsibility for the contractually agreed scope of services.
- Claim Management: Active claim and change management towards the customer.
- Team coordination: Management and coordination of the development team.
- Use of synergies: Use of synergies between customer projects and product development.
- Proposal preparation: Preparation of proposals (with supervision) and presentation on site to customers and partners.
Skills: Development, communication and implementation of product visions; Product Backlog Management; Stakeholder Management; Regular reporting to management and Steering Committees; Requirements analysis & engineering; Planning and documentation of workshops; Professional leadership and coordination of (distributed) project teams and external service providers; Epic Management; User Story specifications; Creation of use cases, support with software testing and User Acceptance Testing (UAT); Release Management and Sprint Planning; Design of TO-BE processes; Process optimization; Planning, design and specification of interfaces to existing and new systems; Identification, assessment and management of project risks; Active claim and change management; Facilitation of sprint planning and reviews; Data migration; Scrum; Kanban; REST API; JSON; XML; BPMN; UML; Jira; Confluence
Fadi S.
Last position:
Development of a production-ready Enterprise Document AI & Recommendation Platform at Freelancer
- Development of a production-ready Enterprise AI solution for the automated processing of invoices and business documents
- Integration of Azure AI Document Intelligence and LLM technologies into existing business processes
- Development of robust REST APIs for automated document processing and system integration
- Extraction, validation, and storage of structured invoice data in Azure SQL as a base for analytics and machine learning models
- Development of an AI-based recommendation engine with machine learning and deep learning to generate personalized product recommendations based on historical purchase data
- Implementation of logging, monitoring, error handling, and validation mechanisms for stable production use
- Collaboration with business teams to define business rules and integrate the solution into existing enterprise processes
Technologies: Python, Azure AI Document Intelligence, Azure OpenAI, Azure SQL Database, REST APIs, Machine Learning, Deep Learning, OCR, Pandas, JSON, Workflow Automation
Ali A.
Last position:
Founder & Architect at Independent AI R&D
- Fully on-premises LLM document-examination platform for a compliance-critical banking domain: agentic LangGraph pipeline with deterministic verification, every AI judgment structured and source-anchored; ~960 automated tests, zero data egress
- GPU throughput engineering (quantized serving, speculative decoding, prefix caching): 9.5x extraction speed-up, 500+ multi-document case files per day on a single A100
- AI-native EDI/EDIFACT integration platform (~116k LOC Java 25 / Spring Boot 4, 1,900+ tests): LLM-drafted partner mappings machine-verified before go-live (DFDL conformance, field-coverage checks, dry runs), ~99.5% byte match on real customer files — replacing weeks of manual mapping per partner
Maciej S.
Last position:
Product Owner at Bundesagentur für Arbeit
- As part of the project, the further development of the identity management system was driven forward. This included a comprehensive refactoring of the interfaces to the connected target systems. In addition, several special systems were successfully connected to the IAM to ensure end-to-end identity and authorization management.
- Technical design and solution proposals for IAM system development
- Requirements analysis and requirements management (IREB, BABOK)
- Alignment of the strategy with the future target architecture (TOGAF)
- Prototyping of solutions
- Documentation of requirements (Innovator)
- Analysis and documentation of requirements and creation of process models (UML, BPMN, ArchiMate)
- Modeling of requirements and system functionalities (OOA/OOD, UML)
- Further development of interfaces (SOAP, REST)
- Carrying out architecture reviews
Fred H.
Last position:
Software Architect and Developer at Personal project
Recurring problem in my own AI-assisted projects: requirements analysis, use cases, and architecture decisions can be created quickly with AI support, but remain difficult to follow and scattered across Markdown files – knowledge is lost as soon as it is no longer in the context window. arknet turns requirements engineering and architecture knowledge into structured, verifiable data instead of plain text: requirements, use cases, and architecture decisions form a consistently linked knowledge graph, traceable from requirement to architecture decision – queryable by both people and AI agents. Technically based on RDF/OWL and a custom MCP server.
Result: Working MCP daemon, Docker image published automatically to GHCR, nine hexagonal modules, eleven ADRs (including an Open-Core licensing model). Requirements engineering and Ubiquitous Language hexagons are active. Public as a Community Edition under Apache-2.0 since 07/2026 (github.com/kogn-io/arknet), together with the Claude Code plugin and GHCR image; Open-Core model.
Label: Java, Maven, RDF, RDF4J, OWL, SPARQL, Model Context Protocol, Spring AI, Docker, GitHub, Git, Claude Code, Obsidian, DDD, Hexagonal Architecture, ArchUnit, JUnit, AssertJ, Interface Development, Software Architecture, Continuous Integration, Knowledge Management
Franz B.
Last position:
Product Development (AI) at Own initiative
AI telephone assistant platform
Claude Code, Google AI Studio, Python, LLM / Voice-AI, PostgreSQL
- Conception and hands-on development of an AI-supported telephone assistant platform (voice AI / LLM) – from idea and architecture to MVP/product.
- Built agentic workflows and full automations with Claude Code and Google AI Studio.
- Also delivered AI-supported work in client engagements: used Claude Code for governance documentation, requirement drafts, and automations.
Karin A.
Last position:
AI Benchmark Engineer | Native language specialist German at Lilt
- Task Engineering: Evaluating Coding Agents.
- Asset Creation: Building realistic task environments using datasets and files in German. Crucially, these assets must remain in the target language to genuinely measure multilingual handling.
- Prompting & Translation: finding failure points where AI does not work, in German.
- Implementation & Verification: Supporting the development of robust solutions (reference implementations) and write highly reliable, deterministic verifier scripts (using rubric-based judging only when strictly necessary).
- Calibration & Execution: Analyze execution logs and calibrate task difficulty (Easy to Very Hard) using standard Terminal-Bench run configurations against various model tiers (Haiku, Opus).
- Quality Assurance: Participation in a rigorous, 4-layer human quality control process (creation, human review, calibration review, and audit) alongside automated LLM-based checks to ensure fairness, grammatical accuracy, and benchmark integrity.
- Linguistic Review: Reviewing AI benchmark tasks across Hindi, Arabic, Japanese, Chinese, Czech and Turkish.
Matthias S.
Last position:
Software Developer and Consultant at CLADE GmbH
- Analysis of the existing CAN communication between microcontrollers
- Analysis of the sensors used and the measured values collected
- Planning the CAN messages for transmitting the measured values
- Iterative adjustment of the microcontroller code to the new CAN messages
- Cross-compilation from x64 to arm64
Timo B.
Last position:
Freelancer (self-employed) at enorin GmbH
- Mendix low-code development / project management
- Managing external resources
- Customer and user management, roles
- Master data entry
- Quote preparation
- Material costing
- Workflows
- Basic CRM functions
- API interfaces (email, SMS, AI chatbot)
- PDF API (.NET development using Aspose.PDF)
- Stakeholder management (dev teams, enorin team, test client)
- Risk management (backend access & sizing, role concepts)
- Testing and staff training
- Creating epics and stories in Confluence
- Jira Scrum planning and management
Discover over 15,000 top freelancers
Statistics of experts using JSON
Aggregated from the professional profiles of matched freelancers.
Experience
19 years
Position duration
5.2 years
Positions per freelancer
14
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Banking and Finance, Automotive
Certification focus areas
Information Technology, Product Development, Project Management
Bachelor's degree or higher
89%
Master's degree or higher
56%
Doctorate
10%
Certifications per freelancer
2
Most common languages
German, English, French
Speak two or more languages
98%
Based on our profile pool as of 26 Sep 2026.
Daily rate distribution
The chart shows how the daily rates of experts in this technology are distributed, based on recent contracts on our platform. Each bar covers a rate range — its height shows the share of experts charging within that range.
Average rates of experts using JSON
Rates are based on recent contracts and do not include FRATCH margin.
The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.
The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.
Calculated based on our freelancers’ daily rates as of 26 Sep 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
JSON experts industry focus
See which industries our matched freelancers work in most often — every figure is calculated live from the freelancers on FRATCH.
- Information Technology (95%)
- Banking and Finance (45%)
- Automotive (44%)
- Manufacturing (42%)
- Professional Services (36%)
- Healthcare (35%)
- Telecommunication (34%)
- Retail (34%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
Data format
JSON is a lightweight, text-based format for representing structured data. Its objects, arrays, strings, numbers, booleans and null values make it easy for applications to exchange information. JSON is human-readable, language-independent and widely used for APIs, configuration files, event payloads and stored documents.
Where it runs
JSON carries data between browsers, mobile applications, backend services and cloud systems. It is a standard choice for REST APIs and is also common in GraphQL responses, webhooks, message queues and serverless workflows. Many databases, automation tools and observability systems can read or produce it directly.
Ecosystem and tooling
Professionals working with JSON usually combine format knowledge with API and data tooling. Their work may include:
- Defining contracts with JSON Schema and OpenAPI
- Transforming payloads with jq, JavaScript or Python
- Validating requests and responses in API gateways
- Mapping JSON to database and event models
- Testing integrations with Postman or automated suites
Project needs
Companies bring in freelance JSON expertise when integrations are unreliable, payloads lack a clear contract or several systems interpret the same data differently. Specialists help during API launches, migrations, partner integrations, e-commerce projects and data pipeline work. They can also document existing formats and reduce errors between teams.
Quality signals
Strong professionals treat JSON as part of a wider data design problem. They use consistent naming, predictable nesting and suitable types, while handling missing, optional and incompatible fields deliberately. They understand encoding, escaping, validation, versioning and security concerns such as excessive payloads or unsafe parsing.
Working together
A JSON assignment benefits from clear examples, sample payloads, API documentation and access to relevant test environments. Remote collaboration works well when teams share schemas, acceptance criteria and contract tests; on-site work may help when the data crosses sensitive internal systems. The right specialist can explain trade-offs clearly and leave maintainable documentation behind.
Frequently asked questions
Need clarity? These are the questions we hear most often about JSON.
JSON is used to exchange structured data between applications and services. Companies rely on it for API requests and responses, configuration, webhooks, event messages and document-oriented data.
JSON is usually more compact and maps naturally to objects and arrays in many programming languages. XML offers richer markup, namespaces and document-oriented features, so the better choice depends on validation, compatibility and the structure of the data.
A strong JSON specialist should understand HTTP, REST APIs, authentication and API testing. Useful adjacent skills include JSON Schema, OpenAPI, JavaScript or Python, databases, message brokers and tools such as jq.
A simple payload cleanup may suit a professional familiar with basic schemas and API testing. Complex integrations need a JSON specialist who has handled versioning, nested data, validation failures, performance and contracts across multiple systems.
Yes. JSON work is often well suited to remote collaboration because teams can share schemas, sample payloads, API documentation and automated tests. On-site collaboration can still be useful when systems contain sensitive data or depend on restricted internal environments.
Review whether the JSON structure is consistent, unambiguous and validated against a clear contract. Ask for examples of API documentation, error handling, compatibility decisions and tests covering optional, invalid and unexpected fields.
JSON can represent complex structures, but deeply nested or very large payloads may become difficult to process and maintain. A specialist should assess pagination, compression, streaming, schema design and whether another format is better for high-volume internal data exchange.
A good JSON freelancer combines precise data modeling with practical integration experience. They clarify requirements, define usable schemas, test real edge cases and explain how changes will affect consuming applications.
The average hourly rate of freelancers who have used JSON in their recent projects is 95 €, which corresponds to a daily rate of about 760 € based on an 8-hour working day.
Of the freelancers who have used JSON in their recent projects, 89% hold at least a Bachelor's degree, 56% hold at least a Master's degree, and 10% hold a doctorate.
On average, freelancers who have used JSON in their recent projects have 19 years of professional experience, with a single engagement typically lasting around 5.2 years.
The most common languages among freelancers who have used JSON in their recent projects are German (98%), English (97%), and French (15%).
The most common industries among freelancers who have used JSON in their recent projects are Information Technology (95%), Banking and Finance (45%), and Automotive (44%).
The most common business areas among freelancers who have used JSON in their recent projects are Information Technology (99%), Product Development (89%), and Quality Assurance (63%).
Main locations of FRATCH Experts, who have recently used JSON
Our freelancers and interim experts are at home all over Germany — available on-site in Berlin, Hamburg, Munich and every major business hub, or fully remote. Choose a city to discover matched specialists, local market insights and up-to-date availability.
Berlin 
Hamburg 
Munich 
Cologne 
Frankfurt 
Stuttgart 
Dusseldorf 
Dortmund 
Essen 
Nuremberg In Austria our freelancers and interim experts support companies from Vienna to Graz — on-site where your project needs them, or fully remote. Choose a city to discover matched specialists, local market insights and up-to-date availability.
Vienna Graz Across Switzerland our specialists are active in Zurich, Geneva, Basel and Bern — working on-site or fully remote. Choose a city to discover matched specialists, local market insights and up-to-date availability.
Zurich Geneva Basel Bern Countries:
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